Error 20003: The following jobs could not be sent: (list of jobs). Please try again or contact your administrator.

Cause

Error 20003 occurs when a completed job cannot be synced because the form (form record) in Salesforce has been deleted. This is very rare and suggests the form was accidentally deleted by a Salesforce administrator as it is not normally allowed.

Solution

There are no known recovery method as it is not possible to completely undelete a form once deleted. Any data contained in the affect completed jobs in devices cannot be synced and would be effectively lost.